Fuze



y 14, 1958 R. E. SWALLOW ET AL 3,382,803

FUZE

Filed May 15. 1967 2 Sheeis-Sheet 1 4% IS A S 6 W a: Q Q I? I 42 2-\ I440 F16. 2. FIG. 2A.

l3 War I w H: I6 7/// l x S INVENTORS. ROBERT E. SWALLOW CLAYTON E. PANLAQUI V. C. MULLER ROY MILLER ATTORNEYS.

y 14, 1968 R. E. SWALLOW ET AL 3,382,803

FUZE

Filed May 15, 1967 2 Sheets-Sheet 2 FIG. 28.

FIG. 2C

Q VII/14s mlr\\\\\\\url '6 w s- Q Q v FIG. 3. l'lOw INVENTORS. 3 ROBERT E. SWALLOW CLAYTON E. PANLAQUI 2o BY V. C. MULLER ROY MILLER ATTORNEYS.

United States Patent FUZE Robert E. Swallow, China Lake, and Clayton E. Panlaqul, Ridgecrest, Calif., assignors to the United States of America as represented by the Secretary of the Navy Filed May 15, 1967, Ser. No. 639,929 4 Claims. (Cl. 10270) ABSTRACT OF THE DISCLOSURE An inertia member is restrained in a safe position by a frustoconical washer which is deformed by the opening of a parachute, a spring then moving the weight to an arm position. In the event of the parachute snagging a tree or the like, the weight is free to move to fire position independent of the rearward pull of the parachute shroud lines.

The invention described herein may be manufactured and used by or for the Government of the United States of America for governmental purposes without the payment of any royalties thereon or therefor.

This invention relates to fuzes and more particularly to improvements in fuzes of the type disclosed in the patent application of Jack A. Myers, Ser. No. 617,749, filed Jan. 17, 1967, now US Patent No. 3,351,017, which is a continuation of Ser. No. 415,840, filed Dec. 3, 1964,

now abandoned.

In the application referred to, a fuze device is disclosed which is armed by the opening of a parachute, the shroud lines moving a mass to arm position. When the payload impacts the ground the shroud lines become slack, permitting the mass to move to fire position by its inertia. While this construction operates satisfactorily upon impact of the payload with the ground or some object, it does not operate if the parachute snags on a tree or other foliage since movement of the mass is dependent upon slackening of the shroud lines.

One of the objects of this invention is to provide a fuze of the type referred to which fires a detonator upon deceleration of the payload .and independent of change in parachute shroud line force.

Another object is to provide a fuze which fires upon tensioning of parachute shroud lines, rather than slackening of same.

A further object is to provide a fuze which operates in substantially the same manner as the fuze referred to upon impact of the payload with the ground.

Still further objects, advantages and salient features will become apparent from the description to follow, the appended claims, and the accompanying drawing, in which;

FIG. 1 is a side elevation of the subject of the inventionj FIG. 2 is a cross section taken on line 2-2, FIG. 1;

FIG. 2A is a like section with the parts in a second position;

FIG. 2B is another like section with the parts in a third position;

FIG. 2C is another like section with the parts in a fourth position; and

FIG. 3 is a section like FIG. 1 of an alternative construction.

Referring now to the drawing, and first to FIG. 1, the environment of the invention is like that disclosed in the application referred to and comprises a grenade or other ordnance device G, including a fuze F, which is suspended by shroud lines a, connected to a parachute 10 which limits the rate of descent to a desired value.

Referring to FIG. 2, the fuze comprises a cup-shaped cap 12, to which the shroud lines are connected, which 3,382,803 Patented May 14, 1968 surrounds a fuze housing 17 which contains a rotor 20 which may move to an armed position by suitable escapement mechanism. A shaft 13 is secured to cap 12 by a lock ring 13b which retains a shoulder 13a in abutting relation to the cap. A malleable deformable frusto-conical safety washer 16 is disposed between a shoulder 15 on the shaft and the upper end wall of the fuze housing. As so far described, the structure and reference character employed are the same as in the application referred to with the exception that shaft 13 is not provided with a firing pin.

The modifications of the fuze disclosed in said application comprise a weight W having a central aperture 40 which slideably surrounds a projection 42 on shaft '13 and a spring S which urges the weight in an upward direction. A firing pin 14a is carried by the weight which engages a stab primer (not shown) carried by the rotor.

In the operation of the apparatus, the parts are in the position shown in FIG. 2 when the device of FIG. 1 is dropped from an aircraft. At a certain distance below the point of drop the parachute deploys, tensioning the shroud lines, and deforming the washer to the position shown in FIG. 2A, the spring moving the weight upward to the position shown. The rotor now moves to a position wherein the stab primer is in alignment with the firing pin.

It will now be assumed that the grenade impacts the ground. The shroud lines now become slack and the inertia of the mass of the cap and weight cause them to move downwardly against the urge of the spring, as shown in FIG. 2B, causing the firing pin to stab the primer. In this mode of operation it is essentially the same as in the application referred to.

It will now be assumed that the parachute snags on a tree or the like, precluding impact of the grenade with the ground. In this mode of operation, as shown in FIG. 2C, the weight, only, moves to firing position, moving downwardly relative to the cap. As will now be apparent, in this mode of operation the fuze operates in distinction to nonoperation of the fuze referred to in said application. In the structure so far described, the shaft, weight and spring are the only modifications to the fuze referred to in said application and fit within the same package. A simplified alternative structure is illustrated in FIG. 3 which may be employed when certain of the parts are redesigned. In this construction, the cap is formed as a disc having suitable perforations through which the shroud lines may extend. The disc is provided with a rivet 130, having a shoulder which engages a frusto-con'ical deformable end wall 160, formed integral with fuze housing 170. As shown, a conical spring S is employed to urge the weight upwardly, however the type of spring shown in FIG. 2 may be employed if desired. The operation is the same as in FIG. 2, the rivet distorting wall to the dotted position when the parachute deploys.

Obviously many modifications and variations of the present invention are possible in the light of the above teachings. It is therefore to be understood that within the scope of the appended claims the invention may be practiced otherwise than as specifically described.

What is claimed is:

1. Apparatus for arming and firing a parachute dropped ordnance device of the type including a fuze housing having a longitudinal axis, a connecting member associated with the fuze housing attached to shroud lines of a parachute adapted to move relatively rearward to the housing along said axis when the parachute deploys, a frusto-conical member interposed between the connecting member and the housing adapted to be deformed when the connecting member moves relatively rearward, and a movable arming member carrying a stab detonator adapted to move from a safe position to an arm position when the 3 frusto-conical member is deformed, the improvements in combination, comprising:

(a) a weight within the housing mounted for movement along said axis relative to the housing and relative to the connecting member,

(b) a spring urging the weight in a rearward direction along the axis adapted to move the weight relatively rearward to an arm position when the frusto-conical member is deformed,

(c) a firing pin carried by the weight adapted to impact the detonator when the weight moves relatively forward,

(d) the construction and arrangement being such that when the parachute snags an object above the ground and thereby further tensions the shroud lines, the weight moves relatively forward against the urge of the spring and independent of relative movement between the connecting member and the housing.

2. Apparatus in accordance with claim 1 wherein the firing pin carried by the weight engages the arming member, prior to arming of the device, and prevents its movement to arm position.

3. Apparatus in accordance with claim 1 wherein the frusto-conical member abuts an end wall of the housing.

4. Apparatus in accordance with claim 1 wherein the frusto-conical member is formed as a integral end wall of the housing.

References Cited UNITED STATES PATENTS 3,351,017 11/1967 Myers 102--76 SAMUEL W. ENGLE, Primary Examiner. 

